#!/usr/bin/env Python
# coding=utf-8

while 1:
    print("this is a division program.")
    c = input("input 'c' continue, otherwise logout:")
    if c == 'c':
        a = input("first number:")
        b = input("second number:")
        try:
            print(float(a)/float(b))
            print("*************************")
        # except ZeroDivisionError:
        #     print("The second number can't be zero!")
        #     print("*************************")
        # except ValueError:
        #     print("please input number.")
        #     print("************************")
        # except (ZeroDivisionError, ValueError) as e:
        except Exception as e:
            print(e)
            print("********************")
    else:
        break